1. Field
The present invention relates to optical communication equipment and, more specifically but not exclusively, to passive wavelength routers.
2. Description of the Related Art
This section introduces aspects that may help facilitate a better understanding of the invention(s). Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.
An access network, also known as a “first-mile network,” connects a service provider's central office to businesses and residential subscribers. Access networks are also sometimes referred to in the literature as subscriber access networks or local loops. The bandwidth demand in access networks has been increasing rapidly, for example, because residential subscribers expect first-mile access solutions to provide high bandwidth and offer media-rich services. Similarly, corporate users demand broadband infrastructure through which they can reliably connect their local-area networks to the Internet backbone.
A passive optical network (PON) is an optical fiber-based access network that can typically provide much higher bandwidth than, e.g., traditional copper-based access networks. The incorporation of wavelength-division multiplexing (WDM) in a PON further increases the available bandwidth. However, WDM-PONs have not been widely commercialized yet, partly due to their relatively high cost compared to conventional systems and partly due to immature device technologies and insufficiently developed network protocols and software to support various commercially viable WDM-PON architectures.